ac6b11037d
Co-authored-by: jbdoumenjou <jb.doumenjou@gmail.com>
183 lines
4.2 KiB
Markdown
183 lines
4.2 KiB
Markdown
# gRPC examples
|
|
|
|
## With HTTP (h2c)
|
|
|
|
This section explains how to use Traefik as reverse proxy for gRPC application.
|
|
|
|
### Traefik configuration
|
|
|
|
At last, we configure our Traefik instance to use both self-signed certificates.
|
|
|
|
```toml
|
|
defaultEntryPoints = ["https"]
|
|
|
|
[entryPoints]
|
|
[entryPoints.http]
|
|
address = ":80"
|
|
[entryPoints.http]
|
|
|
|
[api]
|
|
|
|
[file]
|
|
|
|
[backends]
|
|
[backends.backend1]
|
|
[backends.backend1.servers.server1]
|
|
# Access on backend with h2c
|
|
url = "h2c://backend.local:8080"
|
|
|
|
|
|
[frontends]
|
|
[frontends.frontend1]
|
|
backend = "backend1"
|
|
[frontends.frontend1.routes.test_1]
|
|
rule = "Host:frontend.local"
|
|
```
|
|
|
|
!!! warning
|
|
For provider with label, you will have to specify the `traefik.protocol=h2c`
|
|
|
|
### Conclusion
|
|
|
|
We don't need specific configuration to use gRPC in Traefik, we just need to use `h2c` protocol, or use HTTPS communications to have HTTP2 with the backend.
|
|
|
|
## With HTTPS
|
|
|
|
This section explains how to use Traefik as reverse proxy for gRPC application with self-signed certificates.
|
|
|
|
![gRPC architecture](/img/grpc.svg)
|
|
|
|
### gRPC Server certificate
|
|
|
|
In order to secure the gRPC server, we generate a self-signed certificate for backend url:
|
|
|
|
```bash
|
|
openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout ./backend.key -out ./backend.cert
|
|
```
|
|
|
|
That will prompt for information, the important answer is:
|
|
|
|
```
|
|
Common Name (e.g. server FQDN or YOUR name) []: backend.local
|
|
```
|
|
|
|
### gRPC Client certificate
|
|
|
|
Generate your self-signed certificate for frontend url:
|
|
|
|
```bash
|
|
openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout ./frontend.key -out ./frontend.cert
|
|
```
|
|
|
|
with
|
|
|
|
```
|
|
Common Name (e.g. server FQDN or YOUR name) []: frontend.local
|
|
```
|
|
|
|
### Traefik configuration
|
|
|
|
At last, we configure our Traefik instance to use both self-signed certificates.
|
|
|
|
```toml
|
|
defaultEntryPoints = ["https"]
|
|
|
|
# For secure connection on backend.local
|
|
rootCAs = [ "./backend.cert" ]
|
|
|
|
[entryPoints]
|
|
[entryPoints.https]
|
|
address = ":4443"
|
|
[entryPoints.https.tls]
|
|
# For secure connection on frontend.local
|
|
[[entryPoints.https.tls.certificates]]
|
|
certFile = "./frontend.cert"
|
|
keyFile = "./frontend.key"
|
|
|
|
|
|
[api]
|
|
|
|
[file]
|
|
|
|
[backends]
|
|
[backends.backend1]
|
|
[backends.backend1.servers.server1]
|
|
# Access on backend with HTTPS
|
|
url = "https://backend.local:8080"
|
|
|
|
|
|
[frontends]
|
|
[frontends.frontend1]
|
|
backend = "backend1"
|
|
[frontends.frontend1.routes.test_1]
|
|
rule = "Host:frontend.local"
|
|
```
|
|
|
|
!!! warning
|
|
With some backends, the server URLs use the IP, so you may need to configure `insecureSkipVerify` instead of the `rootCAS` to activate HTTPS without hostname verification.
|
|
|
|
### A gRPC example in go (modify for https)
|
|
|
|
We use the gRPC greeter example in [grpc-go](https://github.com/grpc/grpc-go/tree/master/examples/helloworld)
|
|
|
|
!!! warning
|
|
In order to use this gRPC example, we need to modify it to use HTTPS
|
|
|
|
So we modify the "gRPC server example" to use our own self-signed certificate:
|
|
|
|
```go
|
|
// ...
|
|
|
|
// Read cert and key file
|
|
BackendCert, _ := ioutil.ReadFile("./backend.cert")
|
|
BackendKey, _ := ioutil.ReadFile("./backend.key")
|
|
|
|
// Generate Certificate struct
|
|
cert, err := tls.X509KeyPair(BackendCert, BackendKey)
|
|
if err != nil {
|
|
log.Fatalf("failed to parse certificate: %v", err)
|
|
}
|
|
|
|
// Create credentials
|
|
creds := credentials.NewServerTLSFromCert(&cert)
|
|
|
|
// Use Credentials in gRPC server options
|
|
serverOption := grpc.Creds(creds)
|
|
var s *grpc.Server = grpc.NewServer(serverOption)
|
|
defer s.Stop()
|
|
|
|
pb.RegisterGreeterServer(s, &server{})
|
|
err := s.Serve(lis)
|
|
|
|
// ...
|
|
```
|
|
|
|
Next we will modify gRPC Client to use our Traefik self-signed certificate:
|
|
|
|
```go
|
|
// ...
|
|
|
|
// Read cert file
|
|
FrontendCert, _ := ioutil.ReadFile("./frontend.cert")
|
|
|
|
// Create CertPool
|
|
roots := x509.NewCertPool()
|
|
roots.AppendCertsFromPEM(FrontendCert)
|
|
|
|
// Create credentials
|
|
credsClient := credentials.NewClientTLSFromCert(roots, "")
|
|
|
|
// Dial with specific Transport (with credentials)
|
|
conn, err := grpc.Dial("frontend.local:4443", grpc.WithTransportCredentials(credsClient))
|
|
if err != nil {
|
|
log.Fatalf("did not connect: %v", err)
|
|
}
|
|
|
|
defer conn.Close()
|
|
client := pb.NewGreeterClient(conn)
|
|
|
|
name := "World"
|
|
r, err := client.SayHello(context.Background(), &pb.HelloRequest{Name: name})
|
|
|
|
// ...
|
|
```
|